Six-band armadillo

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Six-band armadillo
Six-banded armadillo (Euphractus sexcinctus)

Six-banded armadillo ( Euphractus sexcinctus )

Systematics
Order : Armored siderails (Cingulata)
without rank: Armadillos (Dasypoda)
Family : Chlamyphoridae
Subfamily : Euphractinae
Genre : Euphractus
Type : Six-band armadillo
Scientific name of the  genus
Euphractus
Wagler , 1830
Scientific name of the  species
Euphractus sexcinctus
( Linnaeus , 1758)

The six-banded armadillo ( Euphractus sexcinctus ) is a species of mammal belonging to the group of armadillos (Dasypoda). It lives in the eastern part of South America and prefers largely open savannah and grasslands, but is also found in various forest areas. As an omnivore , it eats plants as well as insects and small vertebrates, whereby it uses its sense of smell in search of food and often creates small holes. The armadillo also lives underground in specially dug burrows, of which there are several in the animal's area of action . In large areas of South America, the species is also considered to be a disease carrier. The six-banded armadillo population is classified as not endangered.

description

Habitus

Six-banded armadillo in the Pantanal

The six-banded armadillo reaches a head-trunk length of 34 to 49 cm (on average 40 cm), in addition there is a 12 to 30 cm long tail, the weight fluctuates from 2 to 6.5 kg. It is about as big as the nine-banded armadillo ( Dasypus novemcinctus ) and is surpassed only by the caper ( Dasypus kappleri ) and the giant armadillo ( Priodontes maximus ) among the armadillos living today . However, it tends to accumulate fat in captivity and can then weigh up to a maximum of 11 kg. The head has a length of up to 12 cm, and it is also very wide. The muzzle , on the other hand, is quite narrow and still slightly pulled out. Overall, the head has a significantly heavier structure than most other armadillo species. With a maximum length of 4.7 cm, the ears are rather short and set far apart, the distance to one another usually exceeds the length of the ear. The typical head shield is long and triangular in shape and protrudes almost to the tip of the nose, so that it takes up to 80% of the head length. It is formed from large, regularly arranged bone plates. The shield extends behind the ears and widens again in a semicircle in front of the ears, but is slightly drawn in in the area of ​​the eyes. The back armor is divided into three parts with a fixed shoulder and pelvis and six to eight, but often six, movable ligaments in between. It also consists of small bone platelets arranged in rows. The long tail is also armored and there is another band of bone platelets on the neck. Above the tail in the pelvic armor section there are up to four holes in the platelets, which contain glands for a secretion that gives the six-banded armadillo its characteristic odor. The armadillo is generally yellowish-brown in color, and between the individual bone platelets sprout yellowish-tinted, bristle-like hairs. The limbs are relatively short and have five toes each on the front and rear feet. These have strong claws, with the middle claw of the front feet being the longest. The rear foot length varies between 7.5 and 9.2 cm. Female animals have two mammary glands .

Skull and skeletal features

Skeleton of the six-banded armadillo
Six-banded armadillo skull

The skull is very wide and reaches values ​​of up to 7.5 cm at the zygomatic arches , with a length of 12 cm. The rostrum , on the other hand, is rather narrow and drawn out. The dentition differs from that of other mammals and consists of molar-like teeth without tooth enamel , which are relatively strong in the six-banded armadillo. In each half of the jaw there are usually eight to nine teeth in the upper jaw and nine to ten teeth in the lower jaw, for a total of 34 to 38 teeth.

The front limbs in particular are strongly built. On the forearm, at the upper end of the ulna, there is a very extensive and large joint, the olecranon , which takes up about 2.8 cm with a bone length of 7 cm. Such large joints on the forearm are typical of animals with a digging way of life.

Sensory performances and vocalizations

The six-banded armadillo has a bad sense of sight , but a good sense of smell , which is mainly used in foraging for food. In general, an animal utters only a few vocalizations; typical is a grunt that it utters while eating. Young animals also have squeaks and clicks to draw attention to themselves.

distribution

Distribution area

The six-banded armadillo lives in South America and is widespread east of the Andes . The distribution area extends from southern Suriname over the east and middle of Brazil down to Bolivia , the north of Argentina and Paraguay as well as Uruguay , the latter country being the southernmost border. Recently, an expansion of the distribution area in northeastern Brazil across the Rio Gurupí to the west has been observed. The six-banded armadillo is also found there on some islands near the coast, which it reached independently due to its good swimming ability. A small population was introduced in central Chile , but has not proven stable. Another occurrence in Peru is considered unsafe. The preferred habitats are open grasslands and savannahs , especially in the Cerrado and Gran Chaco . The armadillo is also found in various forest landscapes, for example in secondary, dry, but also in deciduous forests. Sometimes it can also be found in the tropical rainforests of the Amazon lowlands and in gallery forests of the Pantanal , but avoids swampy areas. The six-banded armadillo also lives in parts of agricultural areas. In many cases, ecotonal areas are used, such as river banks . The population density in the individual habitats is quite different and generally depends on the biomass available . In the Cerrado region of Brazil it is estimated at around 14 individuals per square kilometer, in gallery and deciduous forests at up to 57 individuals per square kilometer, in the arid Chaco region of Bolivia, however, only one individual on a similarly large area.

Way of life

Territorial behavior

Six-band armadillo

The six-banded armadillo is a solitary animal that is primarily active during the day, but occasionally foraging at night as well. Individual animals have home ranges ( home range ), which tend to get are great. In male individuals, it is significantly larger with up to 96 ha than in females, whose maximum area of ​​action is almost 19 ha. Within their territories, the animals create underground burrows by digging with their forefeet and pushing away the excavated material with their hind legs. The burrows usually reach one to two meters and at an average angle of 32.4 ° into the ground and end in a small chamber that offers just enough space to turn around. The entrances are 20 cm wide and 16 cm high, they are often located between tree roots and face the direction of the wind. A single animal regularly uses a burrow, in one case an 18-fold reuse was observed. However, it has several burrows in a relatively small area. It is known that animals in captivity mark the burrows on the abdomen with the substances from their scent glands, and this is also assumed for animals living in the wild. Aggressive behavior towards conspecifics has only been observed during breastfeeding .

food

As a pronounced omnivore , the diet of the six-banded armadillo consists of vegetable and meat-based foods. However, a large part of its diet is made up of vegetable matter and includes fruits , mushrooms and nuts , but also grain . Investigations into stomach contents from the Brazilian province of Mato Grosso showed mainly seeds and fruits of oranges , papaya and sugar cane ; in total, plant food took up a third of all ingested residues. The proportion of ants and termites was also quite high at 20% , beetles and their larvae and crickets were also found, while spiders were rarely eaten. Overall, the proportion of invertebrates was almost 50%. Also vertebrates were detected, so mainly small mammals such as mice and rats , sometimes even birds and snakes . Whether the vertebrates are actively preyed on in the wild or carrion is eaten is unknown, the six-banded armadillo itself is a bad predator because it lacks the fangs for a deadly bite; but it tears the meat from its prey with its teeth. Animals in captivity have been observed killing rats, and free-living six-banded armadillos in the Pantanal captured domestic chickens in traps that had been released to attract predators . The latter birds, with a weight of around 1.5 kg, represent the largest prey animals to date. On the northeast coast of Brazil, it has also been observed that the armadillo species eats crabs . When foraging for food, the six-banded armadillo uses its good sense of smell and runs back and forth with its nose on the ground, stopping frequently and digging small holes in the ground. Occasionally, it also stands on its hind legs and sniffs the air.

Reproduction

Male and female animals reach sexual maturity at around nine months. It is assumed that the animals are largely ready to mate all year round and that several litters can take place a year, but studies in the Bolivian Chaco region have revealed a shortened, seasonal reproduction phase from October to January for southern populations . Male animals may hunt each other for females; according to observations with camera traps , up to five animals can be involved in such advertising rituals . After the sexual act, the female often visits a nearby burrow, and it has been observed that the male tries to dig it up again. The gestation period is around 60 to 65 days, during which the female builds a nest. As a rule, one to three young animals are born, they are born in the nest chamber and the young remain there for around 90 days. Newborns weigh 95 to 115 g and have closed eyes for the first three weeks of life. The body armor is also still very soft and no hair has yet formed. After around 30 days, the boys eat solid food for the first time, and their weight quadruples in this first month of life. A mother with offspring tries to hide or carry them away if they are disturbed or in danger, transporting the young one by one with her mouth, and can sometimes become very aggressive . The life expectancy of the six-banded armadillo is a maximum of 15 to 18 years.

Predator and enemy behavior

The biggest predators are the jaguar and the puma , but the six-banded armadillo is not the preferred prey of the two big cats. Investigations of 106 excrement sites of the jaguar and 95 excrement sites of the puma in the Paraguayan Chaco region only gave one indication of the capture of this armadillo. The maned wolf also occasionally preyes on a six-banded armadillo. Comparable studies from the Cerrado region in Brazil at 148 poop sites also only provided one evidence. The armadillo species represented only 1.7% of the total exterminated biomass of the maned wolf. Young animals can also be killed by the small rison , which is small enough to penetrate the burrows. Occasionally, the Andean Skunk drives animals out of their shelters. Normally, a six-banded armadillo flees into the next burrow or burrows itself when danger approaches, observant animals get up on their hind legs and sniff the air. When touched, they bite and often defecate and urine , which is interpreted as a reaction to stress .

Parasites

The external parasites mainly include ticks of the genus Amblyomma and fleas of various genera, such as Tunga and Malacopsylla . Internal parasites usually include roundworms , mainly Aspipodera , but also Moennigia or Delicata . In addition, the six-banded armadillo is the carrier of Mycobacterium leprae , which can also cause leprosy in humans. The unicellular Trypanosoma cruzi has also been detected, which causes Chagas disease , which is widespread in South America, but it occurs in the six-banded armadillo with a less dangerous variant. Furthermore, toxoplasmosis pathogens could be identified.

Systematics

Internal systematics of the armadillos according to Gibb et al. 2015
  Dasypoda  
  Dasypodidae  

 Dasypus


  Chlamyphoridae  
  Euphractinae  
  Euphractus  

 Euphractus sexcinctus


   

 Chaetophractus


   

 Zaedyus




   
  Chlamyphorinae  

 Chlamyphorus


   

 Calyptophractus



  Tolypeutinae  

 Priodontes


   

 Tolypeutes


   

 Cabassous







Template: Klade / Maintenance / Style
Historical illustration of the six-banded armadillo from 1902

The six-banded armadillo is the only species of the genus Euphractus within the group of armadillos (Dasypoda), here it also belongs to the family of Chlamyphoridae and to the subfamily of Euphractinae . The next related forms provide the chaetophractus ( Chaetophractus ) and the Pichi ( Zaedyus ) represents the total Euphractinae are as. Schwestertaxon a group consisting of the Chlamyphorinae with the pink fairy armadillo and Tolypeutinae against, inter alia, the ball armadillo ( Tolypeutes ) and the cabassous ( Cabassous ) belong. According to molecular genetic studies, the Chlamyphoridae separated in the Upper Eocene around 37 million years ago. The diversification of the Euphractinae into the genera that exist today began in the Upper Miocene around 11 million years ago. Numerous other genera can be assigned to the subfamily fossil.

A total of five subspecies are recognized today:

The tribal history of the six-banded armadillo goes back to the Middle Pleistocene . The earliest finds include those from the Argentine province of Buenos Aires , where the armadillo species no longer occurs today. Finds from the late Pistocene come from the caves of Lagoa Santa in the Brazilian state of Minas Gerais . Other, similarly old fossil remains come from the Gruta dos Moura and Gruta do Urso caves in the Brazilian state of Tocantins . Bone platelets from the Gruta do Urso Fóssil in the Brazilian state of Ceará date back to the early Holocene .

The six-banded armadillo was first described by Linnaeus in 1758 , but he referred it to the genus Dasypus , the long-nosed armadillos. The genus name Euphractus comes from Johann Georg Wagler in 1830. The word means something like "good bowl" and refers to the back armor, the species name sexcinctus refers to the six movable bands. In the local Guaraní peoples, the armadillo species is called Tatu poju , with poju highlighting the claws on the toes.

Threat and protection

Six-band armadillo at the Cincinnati Zoo

The six-banded armadillo is occasionally hunted by humans as it digs up fields and eats the seeds. However, the meat is rarely consumed by humans because of its supposedly strong taste. A study of indigenous groups in Gran Chaco , Argentina, showed that the amount of six-banded armadillos consumed totaled 3.3% of the ingested biomass over a year, with the armadillo species being consumed on three days within this period. Likewise, the tail is sometimes used to make a fire by creating sparks with the help of flint , but also to transport equipment for creating fire. Furthermore, the armadillo is often the victim of traffic accidents, in the Brazilian state of São Paulo alone it accounts for 37% of all mammals killed by vehicles. Overall, however, the six-band armadillo is widespread and is considered one of the most common representatives of the armadillos. The IUCN classifies the stock as “not endangered” ( least concern ). The six-banded armadillo is found in numerous protected areas, including the Emas National Park in Brazil and the Serra da Capivara National Park , also located in Brazil.

literature

  • Kent H. Redford and Ralph M. Wetzel: Euphractus sexcinctus Mammalian Species 252, 1985, pp. 1-4
  • Mariella Superina and Agustín Manuel Abba: Chlamyphoridae (Chlamyphorid armadillos). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 48-71 (p. 67) ISBN 978-84-16728-08-4

Individual evidence

  1. ↑ a b c d e f g h i j k Paul Smith: Six-banded armadillo Euphractus sexcinctus Linnaeus, 1758. Mammals of Paraguay 5, 2007, pp. 1-16
  2. ↑ a b c d e f g h i j Kent H. Redford and Ralph M. Wetzel: Euphractus sexcinctus Mammalian Species 252, 1985, pp. 1-4
  3. ↑ a b c d e Mariella Superina and Agustín Manuel Abba: Chlamyphoridae (Chlamyphorid armadillos). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 48-71 (p. 67) ISBN 978-84-16728-08-4
  4. ^ SF Vizcaíno and N. Milne: Structure and function in armadillo limbs (Mammalia: Xenarthra: Dasypodidae). Journal of Zoology 257, 2002, pp. 257, 117-127
  5. ↑ IM Medri and Mariella Superina: Euphractus sexcinctus. Edentata 11 (2), 2010, p. 170
  6. ↑ Fernanda Atanaena Gonçalves de Andrade, Marcus Emanuel Barroncas Fernandes, Maria Claudene Barros, Horácio Schneider: A Range Extension for the Yellow Armadillo, Euphractus sexcinctus Linnaeus, 1758 (Xenarthra: Dasypodidae), in the Eastern Brazilian Amazon. Edentata 7, 2006, pp. 27-30
  7. ^ A b Adriani Hass, Flávio HG Rodrigues and Tadeu G. de Oliveira: The Yellow Armadillo, Euphractus sexcinctus, in the North / Northeastern Brazilian Coast. Edentata 5, 2003, pp. 46-47
  8. ^ A b Vinícius Bonato, Eduardo G. Martins, Glauco Machado, Cibele Q. da-Silva and Sérgio F. dos Reis: Ecology of the Armadillos Cabassous unicinctus and Euphractus sexcinctus (Cingulata: Dasypodidae) in a Brazilian Cerrado. Journal of Mammalogy 89 (1), 2008, pp. 168-174
  9. ↑ Tracy S. Carter and Christiane D. Encarnação: Characteristics and Use of Burrows by Four Species of Armadillos in Brazil. Journal of Mammalogy 64, 1983, pp. 103-108
  10. ^ Roberto Guilherme Trovati: Differentiation and characterization of burrows of two species of armadillos in the Brazilian Cerrado. Chilena de Historia Natural 88, 2015, p. 19 doi: 10.1186 / s40693-015-0049-z
  11. ↑ Júlio C. Dalponte and José A. Tavares Filho: Diet of the Yellow Armadillo, Euphractus sexcinctus, in South-Central Brazil. Edentata 6, 2004, pp. 37-41
  12. ↑ Vania Cristina Foster, Grasiela Porfirio, Diego Viana, Pedro Sarmento and Erich Fischer: Yellow armadillos (Euphractus sexcinctus) can predate on vertebrates as large as a chicken. Mammalia 81 (3), 2017, pp. 319–322 ( [1] )
  13. ↑ Erika Cuéllar: Biology and Ecology of Armadillos in the Bolivian Chaco. In: Sergio F. Vizcaíno and WJ Loughry (eds.): The Biology of the Xenarthra. University Press of Florida, 2008, pp. 306-312
  14. ↑ Arnaud Léonard Jean Desbiez, Paulo André Lima Borges and Ísis Meri Medri: Chasing Behavior in Yellow Armadillos, Euphractus sexcinctus, in the Brazilian Pantanal. Edentata 7, 2006, pp. 51-53
  15. ↑ Grasiela Porfirio, Filipe Martins Santos, Leonardo Nascimento, Wanessa Teixeira Gomes Barreto, Pricila Fátima de Souza and Paula H. Santa Rita: An observation of chasing behavior in the yellow armadillo (Euphractus sexcinctus) at Maciço do Urucum, Corumbá, MS, Brazil . Edentata 16, 2015, ( [2] )
  16. ↑ Walfrido Moraes Tomas, Zilca Campos, Arnaud Léonard Jean Desbiez, Danilo Kluyber, Paulo André Lima Borges and Guilherme Mourão: Mating behavior of the six-banded armadillo Euphractus sexcinctus in the Pantanal wetland, Brazil. Edentata 14, 2013, pp. 87-89
  17. ↑ José Luis Poma Urey and Romer Salvador Miserendino Salazar: Avistamientos de una peji (Euphractus sexcinctus Linnaeus, 1758) llevando su cría. Edentata 15, 2014, pp. 66-68
  18. ↑ Andrew B. Taber, Andrés J. Novaro, Nora Neris and Flavio H. Colman: The Food Habits of Sympatric Jaguar and Puma in the Paraguayan Chaco. Biotropica 29, 1997, pp. 204-213
  19. ↑ Flávio HG Rodrigues, Adriani Hass, Ana CR Lacerda, Raquel LSC Grando, Marcelo A. Bagno †, Alexandra MR Bezerra and Wesley R. Silva: Feeding Habits of the Maned Wolf (Chrysocyon brachyurus) in the Brazilian Cerrado. Mastozoologia Neotropical 14 (1), 2007, pp. 37-51
  20. ↑ Gervásio H. Bechara, MPJ Szabó, WV Almeida Filho, JN Bechara, RIG Pereira, JE Garcia and Marcelo C. Pereira: Ticks associated with armadillos (Euphractus sexcinctus) and anteater (Myrmecophaga tridactyla) of Emas National Park, State of Goias, Brazil. Annales of the New York Academy of Sciences 969, 2002, pp. 290-293
  21. ↑ Cristiane Cunha Frota, Luana Nepomuceno Costa Lima, Adalgiza da Silva Rocha, Philip Noel Suffys, Benedito Neilson Rolim, Laura Cunha Rodrigues, Maurício Lima Barreto, Carl Kendall and Ligia Regina Sansigolo Kerr: Mycobacterium lepraect in six-banded (Euphractus) and sex nine-banded armadillos (Dasypus novemcinctus) in Northeast Brazil. MemoriasInstituto Oswaldo Cruz 107 (Suppl. I), 2012, pp. 209-213
  22. ↑ a b Gillian C. Gibb, Fabien L. Condamine, Melanie Kuch, Jacob Enk, Nadia Moraes-Barros, Mariella Superina, Hendrik N. Poinar and Frédéric Delsuc: Shotgun Mitogenomics Provides a Reference Phylogenetic Framework and Timescale for Living Xenarthrans. Molecular Biology and Evolution 33 (3), 2015, pp. 621-642
  23. ↑ Maren Möller-Krull, Frédéric Delsuc, Gennady Churakov, Claudia Marker, Mariella Superina, Jürgen Brosius, Emmanuel JP Douzery and Jürgen Schmitz: Retroposed Elements and Their Flanking Regions Resolve the Evolutionary History of Xenarthran Mammals (Armadillos, Anteaters and Sloths). Molecular Biology and Evolution 24, 2007, pp. 2573-2582.
  24. ↑ Frederic Delsuc, Mariella Superina, Marie-Ka Tilak, Emmanuel JP Douzery and Alexandre Hassanin: Molecular phylogenetics unveils the ancient evolutionary origins of the enigmatic fairy armadillos. Molecular Phylogenetics and Evolution 62, 2012, 673-680
  25. ↑ Esteban Soibelzon, LS Avilla and M. Castro: The cingulates (Mammalia: Xenarthra) from the late Quaternary of northern Brazil: Fossil records, paleoclimates and displacements in America. Quaternary International, 2015 ( doi : 10.1016 / j.quaint.2015.02.052 )
  26. ↑ Paulo V. Oliveira, Ana Maria Ribeiro, Édison V. Oliveira and Maria Somália S. Viana: The Dasypodidae (Mammalia, Xenarthra) from the Urso Fóssil Cave (Quaternary), Parque Nacional de Ubajara, State of Ceará, Brazil: paleoecological and taxonomic aspects. Anais da Academia Brasileira de Ciências 86 (1), 2014, pp. 147–158
  27. ^ Johann Georg Wagler: Natural system of the amphibians, with a preceding classification of the mammals and birds. JG Cotta'sche Buchhandlung, Miinchen, 1830, pp. 1–354 (p. 36)
  28. ^ Mariana Altrichter: Wildlife in the Life of Local People of the Semi-arid Argentine Chaco. Biodiversity and Conservation 15, 2008, pp. 2719-2736
  29. ↑ IM Medri and Mariella Superina: Euphractus sexcinctus. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. ( [3] ), last accessed on April 13, 2013
  30. ↑ James Sanderson: Observations of Xenarthra in the Brazilian Cerrado and Guyana. Edentata 5, 2003, pp. 40-44
  31. ↑ Vanderson Corrêa Vaz, Ricardo Tadeu Santori, Ana Maria Jansen, Ana Cláudia Delciellos and Paulo Sérgio D'Andrea: Notes on food habits of armadillos (Cingulata, Dasypodidae) and anteaters (Pilosa, Myrmecophagidae) at Serra da Capivara National Park (Piauí State , Brazil). Edentata 13, 2012, pp. 84-89

Web links

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